COLT 1000
Intro to Linework I
Intro to Linework I
Over time, this is where a SYP wooden pole tends to be vulnerable to heart rot.
What is right below the ground line?
This is the main objective whenever grounding a piece of equipment.
What is trip the overcurrent device as quickly as possible if the chassis becomes energized?
This is what is referred to as electrical pressure or the difference between in electrical potential between two points.
What is voltage (or electromotive force)?
This is the minimum size and type of cable that should ever be used for purposes of protective grounding.
What is #2 copper?
This is the process of bonding components around worker in order to keep all elements at the same potential in a protective grounding scheme.
What is an Equipotential Zone or EPZ?
A water service line would be marked by the utility using this color.
What is blue?
This is what we do in a 3-phase wye-wye transformer bank configuration with the H2 bushings that are tied together.
What is tie it down to the system neutral?
Per OSHA criteria, rubber gloves for electrical linemen must be electrically tested a minimum of this many months.
What is 6?
What is the line has been grounded?
This is the main difference between a substation and a switchyard.
What is all substations have power transformers to change the voltage?
Using any ordinary phasing meter, AC voltage can be changed to DC voltage in order to check for a faulted primary cable through the use of this device.
What is a DC Hi-Pot adaptor?
This is what the SL bushing on a voltage regulator connects to on a Wye system.
What is the primary neutral?
This is the reason that a handline is the "first thing up and last thing down" when climbing a pole, because your handline is your ____.
What is a lifeline?
This is the type of valve that prevents various components of the boom of a bucket truck or digger derrick from falling when a hydraulic line breaks.
What is the holding valve?
Using Ohms Law, current equals voltage divided by this.
What is resistance?
By OSHA standards, at least this number of employees must be present when performing hands-on gloving work on 14.4kV.
What is at least 2 employees?
Electrically speaking, OSHA requires that wooden poles are considered as this type of object when performing our work.
What is conductive?
This distance is known as the "tolerance zone" which allows the worker to dig with mechanical equipment this close to the utility which is marked.
What is 18 inches?
This is the principle of how a primary winding of an energized transformer induces a voltage into the secondary winding.
What is the principle of electro-magnetic induction?
What is folded? (or creased in some other way)
Insulating line hose is considered by OSHA to be effective for this type of contact when referring to protection for qualified electrical workers.
What is brush contact?
Name one way that voltage is directly corrected in a substation.
What are voltage regulators? Or what is an LTC transformer?
This is the reason that underground systems typically do not employ reclosing schemes.
What is that faults on underground systems tend to be permanent in nature?
This is what an oil-filled GH type sectionalizer is incapable of doing that forces linemen to close in a de-energized line at the nearest upstream recloser rather than at the sectionalizer when the crew is not 100% sure that the line has been cleared of all faults.
What is opening fault current? (and closing in on fault current)
These are the only two OSHA-approved methods for checking wood poles for soundness.
What is the rocking test and the hammer/probe test?
This is the maximum use voltage of a Class 2 rubber glove.
What is 17,000 volts?
This is the reason that AC was chosen over DC as the type of power source for electrical utilities.
What is that it's easy to change the level of voltage?
Incident heat energy levels are based upon fault current, bus spacing, and the duration of the arc which is controlled by this factor.
What is the clearing time of the overcurrent device?
These are the two items of insulating PPE required for Ohio workers to wear when handling grounded conductors on the ground during power restoration activities.
What are rubber gloves and dielectric footwear?
Conductive electrical enclosures (padmounts) must be bonded to CATV and TEL conductive pedestals when they are installed within this many feet of one another.
What is 6 feet?
This is the purpose of an iron core in a transformer.
What is to intensify the magnetic field? (also concentrates and guides the magnetic field).
This is the NESC-required distance that cover-up must be extended when covering a primary line.
What is beyond reach or extended reach distance? or...What is beyond your anticipated work position or extended reach distance? (NESC uses both requirements)
Whenever possible, the lineman shall place himself in this position whenever installing cover-up or performing other work so that he can "fall free" if he happens to slip.
What is "below" the conductor.
There are numerous things that can cause step and touch potentials to exist in a substation. Name two.
What is: copper theft, large imbalances, poor connections on grounding grids and structures, other loose connections, or improper connecting points?
You are performing switching operations to replace a single-phase padmount transformer in an underground loop system. You have is opened, tagged, tested and grounded both primary cables coming in at adjacent locations. This is your next step which will be done at the transformer being replaced.
What is test for voltage and apply grounds?
This is what "sequence coordination" accomplishes on an electronic recloser.
What is it advances the number of counts, allowing the downline recloser to clear the fault.
These are the five required topics to be discussed during a job briefing.
What is hazards, work procedures, special precautions, energy source controls, and PPE?
This is the consensus standard that Ohio and most other states adopt as their electrical safety code for electrical utilities.
What is the National Electrical Safety Code or NESC?
What is air and moisture?
This is the minimum clearance that a primary neutral must have over any roadway subject to truck traffic.
This is the minimum approach distance to ground for 69kV.
What is 3'4"? (three foot, four inches)
This phenomenon is called the "doubling effect" in an underground cable installation.
What is the situation when a lightning strike enters into underground cable? When there is no lightning arrester on the other end, the voltage of the lightning strike doubles back on itself when it returns to the source, always weakening the cable, and sometimes even faulting the cable.
An open-wye/open-delta transformer bank is this efficient when compared to the sum of the kVA of the two transformers (name a percentage).
What is 86%?
While we use rubber gloves to provide against the first point of contact, we typically use this to provide against the second point of contact.
What is insulating cover-up equipment? (or work positioning or bucket trucks, etc.)
Electrical arcs can generate this high of a temperature, which is 3.5 times hotter than the surface of the sun.
What is 35,000 degrees Fahrenheit?
Name the piece of equipment that is intentionally used to help correct a leading power in a transmission substation.
What is a core reactor?
When installing a fault indicator on a single phase underground system, it is important to avoid installing it around both the phase and the concentric neutral for this reason.
What is the currents will cancel out each other?
This is the reason that CT's have always been ratioed as compared to 5 amps (e.g., 200:5).
What is that the original transformer-rated meters were good for 5 amps? Helping to size the CTs directly proportionate to the load.
These are three of the four major components of a TTC zone.
What is advance warning, transition, activity, or termination?
What is an electrical component and an ergonomic component?
A 100kVA 120/240V transformer connected to a 7.2kV potential pull about this much current on the high side when fully loaded.
What is 14 amps? (13.88)
A previously energized line must be grounded unless one of these two exceptions exist that would allow for complete isolation. Name one of the two exceptions.
What is whenever a ground is impractical or it's more hazardous to apply a ground?
Either one of these two events/conditions will cause a voltage rise on a grounded line, potentially shocking or killing the worker if extra precautions are not taken.
What is accidental re-energization or induction? (or lightning)
This is RUS's minimum bending radius for medium voltage cable that is non-Armor type cable: ___ times the overall diameter of the cable.
What is 12?
This is the reason that is undesirable to connect the ground straps on a large wye-configured secondary load in a 120/208 system.
What is that large amounts of current will flow through the ground strap, creating heat, and causing the secondary bushing to work loose and burn up over a period of time?
Type 1 and Type 2 rubber goods are categorized based upon this factor.
What are ozone resistant qualities? Type 1 is natural rubber and Type 2 synthetic rubber.
The person in charge of a job is required to do six things per NESC 421A. Name two of those things.
1. Use proper precautions needed to prevent accidents.
2. Require all employees on the job to follow the rules.
3. Make necessary records and reports.
4. Prevent unauthorized persons from approaching worksite.
5. Prohibit use of improper tools or equipment that have not been inspected or tested.
6. Conduct a job briefing that includes 6 topics.
On a positive pressure inert-gas sealed system, pressure is constantly regulated so that the pressure remains between these two thresholds.
What is +0.5 to +6.5 psi?
A dual element padmount transformer Bay-O-Net fuse detects these two things. Name both.
What is primary and secondary faults? And what is transformer fluid temperature?
While performing switching operations, you determine that you would like to bump up the 7200 volts up 225 volts for less difference at the switch. This would require the step regulator to step forward this number of operations.
What are 5 steps?